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QMX + Backlight dimming

 

Does anyone have an easy safe method of dimming the backlight on the QMX+
Perhaps changing/adding a resistor.
The bright backlight is fine in a well let room or outdoors but in my dimly lit
bat/ham cave it’s hard on the eyes.
Thanks, Dave
 

Maybe you can replace R306 (33 ohm) on the front panel board with a small 100 ohm pot to adjust the brightness. I was thinking of doing it for my QMX (not plus) not necessarily for the brightness but for minimizing the current consumption from the backlight.

73,
Yoon KM6KJI
 

Yes, that is the way to do it. These display's backlight is really bright. I have even used greater resistor there.
--
73 Bojan S53DZ
 

Thank you for the suggestions. I removed R306 and replaced with a 1/8 watt 900 ohm resistor.
On either side of the SMA R306 is a large pad making it easy to solder in a larger resistor. Thank you Hanns!
Backlight brightness is perfect now. Easy on the eyes in a dim lit room.

Dave ve3zzy
 

Hi All.? I have a similar goal-? screen is way too bright.? It does not seem to be the issue of pin 3 hitting the inductor on the power board.? So with r306, there are two solder pads on either side of the resistor.? Safe to assume that those pads are to receive a non-SMD resistor? Of course i have to yank the SMD one off the board, but then i just use the two pads for the non-SMD replacement, correct?
Thanks in advance
JD

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